The present invention rleates to smoking articles such as cigarettes, and in particular, to those smoking articles having a short fuel element and a physically separate aerosol generating means. Smoking articles of this type, and methods and apparatus for preparing them are described in the following patents; U.S. Pat. Nos. 4,708,151 to Shelar; 4,714,082, Banerjee et al.; 4,732,168, Resce; 4,756,318, Clearman et al.; 4,782,644, Haarer et al.; 4,793,365, Sensabaugh; 4,802,568, Haarer et al.; 4,827,950, Banerjee et al.; 4,854,331, Banerjee et al.; 4,858,630, Banerjee et al.; 4,870,748, Hensgen et al.; 4,881,556, Clearman et al.; 4,893,637, Hancock et al.; 4,893,639, White; 4,903,714, Barnes et al.; 4,917,128, Clearman et al.; 4,928,714, Shannon and 4,938,238, Barnes et al., and in Chemical and Biological Studies New Ciqarette Prototypes That Heat Instead Of Burn Tobacco, R. J. Reynolds Tobacco Company, 1988. These smoking articles are capable of providing the smoker with the pleasures of smoking (e.g., smoking taste, feel, satisfaction, and the like).
Cigarettes, cigars and pipes are popular smoking articles which use tobacco in various forms. As discussed in the background sections of the aforementioned patents, many smoking articles have been proposed as improvements upon, or alternatives to, the various popular smoking articles.
Smoking articles described in the aforesaid patents and/or publications employ a combustible fuel element for heat generation and aerosol forming substances positioned physically separate from, and in a heat exchange relationship with, the fuel element. The aerosol generating means normally includes tobacco in various forms such as densified pellets, tobacco dust and tobacco extracts, as well as tobacco flavor modifiers and tobacco flavoring agents and aerosol forming substances such as glycerin. During smoking, heat generated by the fuel element acts to volatilize the aerosol forming substances, thereby providing an aerosol which resembles tobacco smoke. Such smoking articles yield extremely low levels of visible sidestream smoke as well as low levels of FTC "tar".
Many of the aforementioned smoking articles employ a substrate as a carrier for the aerosol forming substance in the aerosol generating means. Typically these substrates have been noncombustible solids, e.g., graphite, carbon, alumina, and the like, which are deemed heat-stable under the operating conditions of the smoking articles using them. In such articles the substrate was exposed to temperatures in the range of 400.degree.-800.degree. C., necessitating a heat-stable material.